package com.itttq.kb.cmpt;

import java.util.regex.Pattern;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import com.itttq.kb.controller.GenericController;
import com.itttq.kb.utils.Constants;

@Component
public class LoginInterceptor extends GenericController implements HandlerInterceptor {  
	private static final long serialVersionUID = -4308107581849196383L;
	
	// 设置非静态界面才需要判断是否登陆
    // 排除不纳入登录验证的路径
    private static final String regExExclude = "\\/login|\\/reg|\\/\\d.html|\\/vc|\\/forget|\\/reset";
    private static final String regEx = "\\/add.html|\\/add|\\/user\\/|\\/reply|\\/edit";
    private static final Pattern pat = Pattern.compile(regEx);
    private static final Pattern patExclude = Pattern.compile(regExExclude);
    
	public LoginInterceptor() {}
  
    /** 
     * 在业务处理器处理请求之前被调用 
     * 如果返回false  从当前的拦截器往回执行所有拦截器的afterCompletion(),再退出拦截器链 
     *  
     * 如果返回true 
     *    执行下一个拦截器,直到所有的拦截器都执行完毕 
     *    再执行被拦截的Controller 
     *    然后进入拦截器链, 
     *    从最后一个拦截器往回执行所有的postHandle() 
     *    接着再从最后一个拦截器往回执行所有的afterCompletion() 
     */  
    @Override  
    public boolean preHandle(HttpServletRequest request,  
            HttpServletResponse response, Object handler) throws Exception {  
        String url=request.getRequestURL().toString();
        if(regEx!=null && pat.matcher(url).find() && !patExclude.matcher(url).find()) {
        	Object obj = this.getSession(request, Constants.SESSION_USER);
        	if(null == obj) {
	        	// 记录上一次登陆地址
	        	this.setSession(request, Constants.SESSION_URL_LAST, url);
	        	request.getRequestDispatcher("/login.html").forward(request, response);
	        	return false;
        	}
        }
        return true;
    }
  
    //在业务处理器处理请求执行完成后,生成视图之前执行的动作   
    @Override  
    public void postHandle(HttpServletRequest request,  
            HttpServletResponse response, Object handler,  
            ModelAndView modelAndView) throws Exception {  
    }  
  
    /** 
     * 在DispatcherServlet完全处理完请求后被调用  
     *  
     *   当有拦截器抛出异常时,会从当前拦截器往回执行所有的拦截器的afterCompletion() 
     */  
    @Override  
    public void afterCompletion(HttpServletRequest request,  
            HttpServletResponse response, Object handler, Exception ex)  
            throws Exception {
    }
    
    public static void main(String[] args) {
    	String url = "http://localhost:8001/user/1.html";
    	System.out.println(pat.matcher(url).find());
    	System.out.println(!patExclude.matcher(url).find());
    }
}
